C++ 关键字（标识符）

asm	auto
bool	break
case	catch	char	class	const	const_cast	continue
default	delete	do	double	dynamic_cast
else	enum	explicit	export	extern
false	float	for	friend
goto
if	inline	int
long
mutable
namespace	new
operator
private	protected	public
register	reinterpret_cast	return
short	signed	sizeof	static	static_cast	struct	switch
template	this	throw	true	try	typeid	typename
union	unsigned	using
virtual	void	volatile
wchar_t	while

变量和常量命名规则：

1.不能使用关键字

2.由字母、数字、下划线组成

3.数字不能放在首位

4.区分大小写

5.最好做到见名知义